I have the exact same set up as far as engine, gears and tranny. The 3570 made it shift much like it was running stock 32" tires. Im running 315.70.17 on stock rubicon 5 spokes. The 3.73 isnt bad but make sure you measure the tire, under load, and with what tire psi you need to get full tread contact. I wouldnt hesitate to buy another one. Plus the tpms download was free so no more getting the idiot light when we air down at the trails.

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Thanks for the response. I lifted mine and installed 33's as soon as we bought it. I've been looking at tires and trying to decide on a size. I've been looking at tire specs and trying to find something lightweight in a "34" or "35" inch tire. I've just about decided on Nitto Trail Grapplers. They make a 295/70-17 which is about 33 1/2 inches tall and a 315/70-17 that's about 34 1/2 inches tall. Both would be a step up from our 305/65-17 BFG's which are about 32 1/2 inches tall, so my speedometer/odometer and shift points would be "off" even more.

 

The 33.5 would b off alittle but you definitely would notice the 34.5 being off

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Thanks for sharing! I have 315/70r17 BFG ATs in the mail and am running 3.73 on my 2015 sport. I have been looking for someone to make a recommendation like this. Do you happen to have a reco on a tire carrier?

 

For sure. My JKU came with "32's" which were actually around 31 1/2 inches tall. So I'm gonna actually be around 2 to 3 inches taller than the OEM tires.
Also, one more question. Can you adjust the shift points of the automatic trans with the Superchips Flash Cal or do you have to upgrade to the Flash Pac to do that?

 

I can recommend a tire carrier. When I moved up to 35" tires I looked for what seemed like forever and finally decided on the LoD 4th Generation rear bumper/tire carrier. I got it in the full width for rear quarter panel protection. I did not go with the linked version for several reasons. I wanted to be able to carry gas on both sides of the tire, I wanted to be able to mount a basket on it too, and I didn't want it attached to the tailgate in case I take a hit to the tire which would transfer the damage right to the tailgate. It functions flawlessly, no rattles or shakes, and it looks great. I also got with the cut outs for less but I haven't added the rigids yet.

 

If you want any engine tuning then you will have to upgrade to the tuner. When you put the correct tire size it adjusts your shift points accordingly.

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Ok, thanks. I had a Superchips tuner on my last truck and I wasn't impressed with the engine tuning. But being able to raise my shift points seemed to make an inprovement in how the truck drove. I ordered a Flash Cal but I'll probably upgrade later.

 

Made a huge difference in our 13 auto running 35's. Throttle response and shifting is way way way better.

 

This thread has inspired me to upgrade my flashcal to a flashpaq while it's still half price. I'm installing the 91 tune now as the 87 performance is not available. Can't wait to see the difference.

Thanks, K9Jeeper, for the review.